1. Field
Embodiments of the present invention relate to an improvement of a structure of a rear lighting device for a vehicle, such as a motorcycle.
2. Description of the Related Art
A conventional structure of a rear lighting device for a motorcycle has been known to include a turn signal lamp lens including a clear lens portion that allows a bulb to be seen therethrough from the outside, and a cut portion that makes it difficult to see the bulb by use of diffuse reflection (see, for example, Japanese Patent No. 3580516).
According to Japanese Patent No. 3580516, a turn signal lamp is provided with a clear lens portion and a cut portion. The clear lens portion is transparent and located in a center portion of a lens in such a manner as to face a bulb. The cut portion is located in a peripheral portion of the lens in such a manner as to surround the clear lens portion, and has projections and depressions which cause diffuse reflection.
For example, consider a case where a combination lamp is formed by integrating the turn signal lamp with a tail lamp, and where the light emission area of the turn signal lamp is made large for improving the visibility of the turn signal lamp when viewed from rear of the vehicle. In such a case, it is conceivable that the clear lens portion and the cut portion greatly differ from each other in light emission intensity.
As shown in Japanese Patent No. 3580516, the clear lens portion is located to extend in a vertical direction with respect to the ground. Accordingly, when a person views the turn signal lamp obliquely from behind and above the motorcycle, the person can see both the clear lens portion and the cut portion. Hence, light from the bulb directly reaches the eyes through the clear lens portion, and the difference in light emission intensity between the clear lens portion and the cut portion is recognized, as mentioned above. For this reason, it is conceivable that the difference in light emission intensity may be more visible in some cases.
Moreover, in some cases, in order to improve the marketability of the rear lighting device as described above, the rear lighting device is desirably designed to look slim and simple when viewed by a person from behind the motorcycle, thereby providing the rear portion of the vehicle with a light impression.